The propagation of a debris flow triggered by the intense rainfall on 25th October 2011 in the eastern Liguria region was studied by numerical means. The site and the soil were preliminarily characterized in order to estimate the parameters of the rheological model. Then, a two-dimensional numerical model was used to simulate the time development of the velocity and the thickness of the flowing material. The supplement of additional material to the propagating debris flow was considered to investigate the effect of the debris entrainment on the run-out process and on the kinetic energy of the flow. In particular, kinetic energy is used as a criterion to infer the riskiness of the debris flow.